1. Technical Field of the Disclosure
The present disclosure relates generally to stimuli-responsive materials, and more particularly, to embodiments of a shape-memory product, where one embodiment comprises a matrix component such as epoxy and a filler component in the form of a network of nanofibers that interpenetrates the matrix component and conducts electrical stimuli thereon.
2. Description of Related Art
As discussed in the Provisional Application, shape memory polymers (SMPs) are stimuli-responsive materials that have the ability to change shapes on demand.[1-5] Although having a number of intrinsic advantages such as large deformation strain (actuation amplitude), low density and low manufacturing cost, some major limitations of SMPs are still present and impose great challenges to their large-scale applications.[4, 6] Some of the key limitations include (1) small recovery stresses due to low rubbery moduli (0.1˜10 MPa), (2) low recovery speed, primarily due to poor thermal conductivities, and (3) inertness to electromagnetic stimuli (in contrast with shape memory alloys or SMAs), due to the insulating nature of most polymeric materials.
Research efforts have been undertaken in response to these challenges. For example, with regard to challenge (3) listed above, electro-active materials systems have been developed[7] by combining SMPs with conductive fillers including carbon black,[8-11] carbon nanotubes (CNTs),[12, 13] short carbon fibers,[8, 10, 14] nickel,[9, 15] and polypyrrole.[13, 16]
There is a need, therefore, for shape memory materials and products with improved conductivity and recovery performance.